Digital Commons Network^™

Enhancing The Performance Of Poly(3-Hexylthiophene) Based Organic Thin-Film Transistors Using An Interface Engineering Method, Eyob Negussie Tarekegn

All Dissertations

An original design and photolithographic fabrication process for poly(3-hexylthiophene-2, 5-diyl) (P3HT) based organic thin-film transistors (OTFTs) is presented. The structure of the transistors was based on the bottom gate bottom contact OTFT. The fabrication process was efficient, cost-effective, and relatively straightforward to implement. Current–voltage (I-V) measurements were performed to characterize the primary electronic properties of the transistors. The measured mobility of these transistors was significantly higher than most results reported in the literature for other similar bottom gate bottom contact P3HT OTFTs. The higher mobility is explained primarily by the effectiveness of the fabrication process in keeping the interfacial layers …

The Role Of Fatty Acid Metabolism In The Pathogenesis Of Trypanosoma Brucei, Nava Poudyal

All Dissertations

Trypanosoma brucei is the protozoan parasite that causes African Sleeping Sickness in humans and nagana, a wasting disease in cattle. T. brucei completes its life cycle in two hosts, mammals and the tsetse fly insect vector. Due to the geographical restriction of the tsetse fly, the disease is endemic in sub-Saharan Africa. Both the insect and mammalian forms of the parasite need fatty acids to anchor their surface proteins. We worked on three projects on fatty acid metabolism and its role in immune evasion strategies of T. brucei. First, we assessed the role of T. brucei surface proteins in …

Permanently-Installed Distributed Pressure Sensors For Downhole Applications, Xuran Zhu

All Dissertations

Technology advancements (e.g., hydraulic fracturing and horizontal drilling) to recover unconventional oil and gas (UOG) resources are critical in maintaining future U.S. oil and gas production levels. Permanently installed distributed downhole pressure sensors could monitor fracture propagation, assess the effectiveness of hydraulic fracturing, and optimize hydraulic fracturing placement so that overall UOG recovery efficiency can be increased. However, the harsh environment (high temperatures, high pressures, strong vibration, and presence of brine, mud, debris, hydrate, and various gases), the long data telemetry distance, and the requirements of reliability and service lifetime make the downhole monitoring a very challenging task. To combat …

Metabolic Engineering Of Yarrowia Lipolytica For Enhanced Peroxisomal Production Of Polyhydroxyalkanoates, Michael Spagnuolo

All Dissertations

Traditional chemical processes are made inefficient by the generation of side products and reactions that fail to reach completion. Bioprocesses, on the other hand, lose product potential due to the necessity of growing the organism required to produce the desired compounds. The field of metabolic engineering often seeks to alter this balance between product formation and cell growth to generate more product from the same quantity of feed (reagent). In addition to balance, such organisms may also be engineered to produce the desired products from nontraditional substrates, such as waste compounds. In resource-poor environments, the ability to produce a wanted …

Exploring Soil-Tree Interactions After Applying Organic Matter Amendments To Peach Orchards In The Subtropical Climate Of The Southeastern United States, Brian Lawrence

All Dissertations

Soil disturbance from the cultivation and intensive management of orchards in hot and humid subtropical climates can reduce soil organic matter (OM). This research explored how the addition of OM amendments impact soil and tree parameters in two field studies and how proximity to OM may elicit unique genomic response of peach roots in a split-root pot study. The first field study applied two rates of compost (1x and 2x) and subsequently reduced fertilizer applications annually to a virgin and replant orchard location. While both compost rates successfully replaced fertilizers, only the 2x rate in the replant location increased soil …

Needs Assessment For Systematic Cultural Competence Training In The Field Of Applied Behavior Analysis, William Edwards

All Dissertations

As the prevalence rates of Autism Spectrum Disorder (ASD) continue to increase, Applied Behavior Analysis (ABA) is now universally recognized as the most effective and empirically based treatment option for children. This recognition has led to greater accessibility to services for families, a broader range of funding sources, increased client diversity, and an unprecedented demand for qualified service providers. With this increased demand for qualified providers and the increased diversity of clients, a needs assessment for cultural competence training was conducted.

The Needs Assessment for Systematic Cultural Competence Training in Applied Behavior Analysis captured demographic information related to providers and …

Ligand-Promoted Dissolution Of Uranyl Phosphate Across Scales, Brennan Ferguson

All Dissertations

The formation of uranyl phosphate precipitate is a remediation strategy because the low solubility of uranyl phosphate minerals, like chernikovite, limits the mobility of uranium in contaminated soils. However, organic ligands can complex with aqueous metal cations to form more soluble species. For example, citrate is a commonly occurring organic ligand produced by plants and microbes that increases the solubility of uranium and therefore the dissolution of uranyl phosphate minerals in the uranyl phosphate-citrate system. This effect is an important control on the mobility of uranium in organic-rich, and near-surface vegetated environments. Nevertheless, key aspects of the citrate-uranyl phosphate system …

Machine Learning Solutions For Biomedical Applications, Madeleine St. Ville

All Dissertations

This dissertation proposes three novel Bayesian modeling techniques to addresses the challenges arising from the complex, underlying features of biomedical data. These models are motivated by three different biomedical studies. The first is an analysis of data collected from six efficacy and safety clinical trials of buprenorphine maintenance treatment for opioid use disorder. The focus of this study is to overcome the problem of non-adherence by trial participants that, if left unaccounted for, obscures the true effect of buprenorphine on illicit opioid use. The second study is the assessment of hemodialysis cannulation skill through the use of a sensor-based simulator …

Mechanics Modeling Of Non-Rigid Origami: From Qualitative To Quantitative Accuracy, Jiayue Tao

All Dissertations

Origami, the ancient art of paper folding, has recently evolved into a design and fabrication framework for various engineering systems at vastly different scales: from large-scale deployable airframes to mesoscale biomedical devices to small-scale DNA machines. The increasingly diverse applications of origami require a better understanding of the fundamental mechanics and dynamics induced by folding. Therefore, formulating a high-fidelity simulation model for origami is crucial, especially when large amplitude deformation/rotation exists during folding.

The currently available origami simulation models can be categorized into three branches: rigid-facet models, bar-hinge models, and finite element models. The first branch of models assumes that …

Multi-Criteria Performance Evaluation And Control In Power And Energy Systems, Payam Ramezani Badr

All Dissertations

The role of intuition and human preferences are often overlooked in autonomous control of power and energy systems. However, the growing operational diversity of many systems such as microgrids, electric/hybrid-electric vehicles and maritime vessels has created a need for more flexible control and optimization methods. In order to develop such flexible control methods, the role of human decision makers and their desired performance metrics must be studied in power and energy systems. This dissertation investigates the concept of multi-criteria decision making as a gateway to integrate human decision makers and their opinions into complex mathematical control laws. There are two …

Statistical Methods For Modern Threats, Brandon Lumsden

All Dissertations

More than ever before, technology is evolving at a rapid pace across the broad spectrum of biological sciences. As data collection becomes more precise, efficient, and standardized, a demand for appropriate statistical modeling grows as well. Throughout this dissertation, we examine a variety of new age data arising from modern technology of the 21st century. We begin by employing a suite of existing statistical techniques to address research questions surrounding three medical conditions presenting in public health sciences. Here we describe the techniques used, including generalized linear models and longitudinal models, and we summarize the significant associations identified between research …

Quantifying And Identifying Mechanisms Of Resistance To Thrips (Thysanoptera: Thripidae) In Landraces Of Upland Cotton (Gossypium Hirsutum), Sophia Christian

All Dissertations

Throughout the southeastern USA, tobacco thrips (Frankliniella fusca Hinds) are the primary thrips (Thysanoptera: Thripidae) pest species of cotton (Gossypium spp.) seedlings and are often detrimental to the establishing crop. In 2020, cotton yield losses from thrips and their management cost USA growers $70.7 million. Heavy reliance on prophylactic insecticides, primarily used as seed treatments, has led to insecticide-resistant populations of tobacco thrips. Currently, no known commercial cotton cultivar provides protection to prevent injury from thrips feeding. A sustainable, alternative management tactic is needed to address insecticide-resistant populations of and reduce damage from thrips in cotton. Our research evaluated day-neutral, …

A New Comprehensive And Practical Taxonomy Of Demands Healthcare Professionals Experience: The Development Process And Testing Using Machine Learning, Phoebe Xoxakos

All Dissertations

Given the complex (Ratnapalan & Lang, 2020) and high stress environment of healthcare organizations (Freshwater & Cahill, 2010), a better understanding of the conditions in which healthcare professionals work is important. Although previous research has resulted in somewhat limited categories of the demands on healthcare professionals (Borteyrou et al., 2014; Shanafelt et al., 2020), a comprehensive taxonomy that covers the breadth and depth of demands is lacking. Using longitudinal data collected over 28 measurement waves spanning two years during the COVID-19 pandemic, the present studies outline the development of a taxonomy based on an in-depth literature review of related workplace …

Identity Tensions And Negotiations Of English Teachers In Costa Rica Through Narrative Inquiry, Hazel Vega Quesada

All Dissertations

This study examined the identity tensions and negotiations of novice three English teachers in Costa Rica, and English as a foreign language context. Grounded in a Communities of Practice framework, this research describes how teachers’ identities are constrained and enabled in complicated academic, social, and political settings. In this study, identity tensions referred to dilemmas that juxtaposed internal and external expectations, values, and practices. Negotiations referred to teachers’ choices, proposals, and changes that denoted their appropriation or contestation of practices and meanings of their communities of practice. I used narrative inquiry to collect and analyze teachers’ experiences learning English and …

Infusing Kirigami Principles Into Design Of Mechanical Properties, Hesameddin Khosravi

All Dissertations

The emergence of mechanical metamaterials — which derive their properties primarily from the underlying architecture rather than the constituent material — has unleashed a new era of material design and functionalities. To fully materialize the promising potentials of metamaterials, it is crucial to develop versatile, scalable, and easy-to-fabricate methods that can both generate and tailor the underlying periodic architecture. To this end, we propose the use of kirigami — a popular recreational art of cutting and manipulating paper — as a platform to create periodicity and super-stretchability. Kirigami has become a design and fabrication framework for constructing metamaterials, robotic tools, …

Understanding The Aspirations And Challenges Of Michigan’S Black School Superintendents: A Toolkit For Building Equity In The Superintendency, Kevin Simmons

Dissertations

Black superintendents are significantly underrepresented in our nation’s schools. Despite a slight increase in representation of female Black superintendents, minorities of all races continue to be underrepresented (Tienken & Domenech, 2020). In this study, I examined the experiences of Black superintendents in Michigan who currently hold superintendent roles, along with the obstacles they faced and their personal characteristics and associated factors that attributed to their resilience and longevity in their role as superintendent. Using a phenomenological qualitative study approach of personal and confidential interviews and survey questions of 12 Black superintendents, data was collected to formulate a toolkit for aspiring …

The Speculative Artifact 2022, Students Of Risd, Risd Archives

All Student Newspapers

The Speculative Artifact was a student publication created for the Graphic Design seminar/studio Critical Issues Studio, taught by Anther Kiley in Fall 2022. The publication features designs and concepts for artifacts of the future created by students. Artifacts include language aids, a sex worker kit, food packaging, a garden pack, style-transferred furniture, a post-taste apartment, a maze sculpture, a personality magazine, animal-human cohabitation, signage, a friend-dating system, coding tech, a transhuman sticker book, and television programming with animal languages

El Leñador, December 2022, El Leñador Staff

El Leñador Newspaper

El Leñador is an English and Spanish newspaper produced by Humboldt State University students. Our staff cover and provide news to Latinx and other diverse communities on campus and in Humboldt County. We are committed to providing relevant news and expanding the representations and stories told about people of color and other marginalized groups. Our work helps create more social, political and cultural diversity in local media.

El Leñador es un periodico en español y inglés producido por estudiantes de la Universidad Estatal de Humboldt. Nuestro personal cubre y provee noticias a la comunidad Latinx y otras comunidades diversas en …

The Antimicrobial Resistance Plasmid Mobilome Of Salmonella Enterica And Related Enteric Species And Factors That Influence The Transfer Efficiency., Suad Algarni

Graduate Theses and Dissertations

The dynamic distribution of antimicrobial resistance genes in Salmonella enterica is considered a public health risk. S. enterica is one of the most important etiological agents of foodborne illness and has a critical impact on global human health. In S. enterica and related species, mobile genetic elements (MGEs) serve as primary vehicles for the dissemination of antibiotic resistance genes in the bacterial evolution. This dissemination can be impacted by different selective pressures that leads to diverse antibiotic response phenotypes. This project focusses on the dynamics of antimicrobial resistance genes, particularly exploring the transfer efficiency of multidrug resistance plasmids in S. …

Only Shades Of Red, Ally Casa, Special Collections, Fleet Library

9th Baker & Whitehill Student Artists' Book Contest 2023

Entry for the 9th Annual Baker & Whitehill Student Artists' Book Contest. Opening Reception Thursday, March 02, 2023, Fleet Library, Main Reading Room. Juror: Andre Lee Bassuet.

She Saw Red All Around Her, Clare Hawkinson, Special Collections, Fleet Library

9th Baker & Whitehill Student Artists' Book Contest 2023

Entry for the 9th Annual Baker & Whitehill Student Artists' Book Contest. Opening Reception Thursday, March 02, 2023, Fleet Library, Main Reading Room. Juror: Andre Lee Bassuet.

Caught In The Canopy, Daniella Pozo, Special Collections, Fleet Library

9th Baker & Whitehill Student Artists' Book Contest 2023

Entry for the 9th Annual Baker & Whitehill Student Artists' Book Contest. Opening Reception Thursday, March 02, 2023, Fleet Library, Main Reading Room. Juror: Andre Lee Bassuet.

Building Memories, Mariam Devadze, Special Collections, Fleet Library

9th Baker & Whitehill Student Artists' Book Contest 2023

Entry for the 9th Annual Baker & Whitehill Student Artists' Book Contest. Opening Reception Thursday, March 02, 2023, Fleet Library, Main Reading Room. Juror: Andre Lee Bassuet.

Best Wishes, Helen Fan, Special Collections, Fleet Library

9th Baker & Whitehill Student Artists' Book Contest 2023

Entry for the 9th Annual Baker & Whitehill Student Artists' Book Contest. Opening Reception Thursday, March 02, 2023, Fleet Library, Main Reading Room. Juror: Andre Lee Bassuet.

It’S All In Your Mind, Deanne Fernandes, Special Collections, Fleet Library

9th Baker & Whitehill Student Artists' Book Contest 2023

Entry for the 9th Annual Baker & Whitehill Student Artists' Book Contest. Opening Reception Thursday, March 02, 2023, Fleet Library, Main Reading Room. Juror: Andre Lee Bassuet.

I Went Fishing, And Caught A Shooting Star, Leah Lara, Special Collections, Fleet Library

9th Baker & Whitehill Student Artists' Book Contest 2023

Entry for the 9th Annual Baker & Whitehill Student Artists' Book Contest. Opening Reception Thursday, March 02, 2023, Fleet Library, Main Reading Room. Juror: Andre Lee Bassuet.

Every Shade Of Pink On Me, Roy Larmour, Special Collections, Fleet Library

9th Baker & Whitehill Student Artists' Book Contest 2023

Entry for the 9th Annual Baker & Whitehill Student Artists' Book Contest. Opening Reception Thursday, March 02, 2023, Fleet Library, Main Reading Room. Juror: Andre Lee Bassuet.

A Or B, Gahyeon (Gabi) Lee, Special Collections, Fleet Library

9th Baker & Whitehill Student Artists' Book Contest 2023

Entry for the 9th Annual Baker & Whitehill Student Artists' Book Contest. Opening Reception Thursday, March 02, 2023, Fleet Library, Main Reading Room. Juror: Andre Lee Bassuet.

Concrete Poetry: A Manifesto, Yining Li, Special Collections, Fleet Library

9th Baker & Whitehill Student Artists' Book Contest 2023

Entry for the 9th Annual Baker & Whitehill Student Artists' Book Contest. Opening Reception Thursday, March 02, 2023, Fleet Library, Main Reading Room. Juror: Andre Lee Bassuet.

Memotone Musicassette, Maggie Weng, Special Collections, Fleet Library

9th Baker & Whitehill Student Artists' Book Contest 2023

Entry for the 9th Annual Baker & Whitehill Student Artists' Book Contest. Opening Reception Thursday, March 02, 2023, Fleet Library, Main Reading Room. Juror: Andre Lee Bassuet.